First of all, I assume you're already familiar with the article on

Odds & Outs and its accompanying video and quiz? If not, do check it out.

Multiplying your outs by 2 or 4 should be accurate enough as a rule of thumb to get the probability of hitting your outs as a percentage. If you want to get it as odds that can be compared to the pot odds, I think the best way is to just learn the odds for the most common draws by heart:

Overcards (6 outs): 7:1

OESD (8 outs): 5:1

Flushdraw (9 outs): 4:1

Flushdraw + gutshot (12 outs): 3:1

Flush draw + pair (14 outs): 2.5:1

Flush draw + OESD (15 outs - a monster draw): 2:1

Lesser draws like gutshots (11:1 odds) are rarely worth chasing, so I think you can ignore them for now.

*Originally posted by mytylynRNMD*

My problem is what odds you calculate on flop...

because you can calculate odds for turn and odds for turn and river

Always calculate your odds for the next street (flop to turn or turn to river), unless you're faced with an all-in. If that's the case, the odds from flop to river are:

Overcards (6 outs): 3:1

OESD/Flush draw (8/9 outs): 2:1

Flush draw + gutshot or better (>12 outs): 1:1 - go for it!

*Originally posted by mytylynRNMD*

i know that on turn odds will change ( bet , other outs...) but also not all hands go with bet on every street

Are you talking about pot odds? The odds themselves do not change at all depending on any bets.

*Originally posted by mytylynRNMD*

still have to learn about implied odds, fold odds , equity....(any help
)

You can find the related articles here:

Implied Odds
Introduction to Ranges
Combos & Card Removal
Introduction to Equity
Equity: Final Calls
If you have any questions, don't hesitate to ask.

EDIT: Oh, and by the way, do I assume correctly that you're playing cash games?

If you aren't, you can't really follow the rules about pot odds to the letter. Draws are played differently in tournaments.